


This Dream Come True

by GemNika



Category: Bleach
Genre: Adorable Mayuri, Family Feels, Family Fluff, Gen, Inspired by Fanart, Mild Gore, Nemuri Project, Papayuri AU, Science Experiments
Language: English
Status: Completed
Published: 2018-02-06
Updated: 2018-02-06
Packaged: 2019-03-14 13:32:44
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,841
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13591098
Author URL: https://archiveofourown.org/users/GemNika/pseuds/GemNika
Summary: Papayuri AU. He'd finally succeeded in the Nemuri Project. He'd created her on his seventh attempt. Now what was he supposed to do with his successful experiment?





	This Dream Come True

**Author's Note:**

  * For [cybzilla](https://archiveofourown.org/gifts?recipient=cybzilla).



> You guys can thank LittlePrincessNana and lisaflowers for this little one-shot.
> 
> This story was inspired by the art by cybzilla on tumblr, that can be found here: cybzilla.tumblr.com/image/160460254102
> 
> Welcome to the Papayuri AU, where many things are the same, except Mayuri actually gives at least two shits about Nemu, and is weirdly adorable about it.

The project was a complete success, and he couldn't have been happier about that. She was the seventh attempt in his Nemuri project, and the only one to make it past gestation. Mayuri had known it would work out eventually. That's what science was for anyway - experimentation, adaptation, research. And now that everyone else was gone, he could give the little infant he'd created a thorough once-over.

Nemuri Seven was three months old and she could be taken out of her sleeping cylinder, so he was going to examine her. He hadn't wanted to chance over-handling the infant only to find that her immune system was compromised, so he'd ordered all shinigami that worked beneath him to never touch her.

She was fed through a machine. Bathed and changed through machines. This would be her first human contact.

Mayuri just didn't trust anyone else to handle this particular assessment.

His white-painted hands trailed across the glass surrounding Nemuri Seven. She looked like a healthy infant. Her eyes were focused solely on him. The printouts of her brainwaves earlier that day showed promising results. She was intelligent.

"No crying," he whispered to Nemuri Seven. No one was around, having been dismissed by him for the day. Thankfully, no one questioned whether or not he could handle the infant. The machines were programmed by him, after all. "I'm opening this now."

He wasn't sure why he felt the need to tell her what he was doing. Mayuri didn't really care what his test subjects felt while he examined them. Nemuri gurgled and rolled from her back onto her side just as he reached for the release button. His finger stopped, hovering over the button, while he watched her chubby legs wriggle where they peeked out of her diaper.

"What are you doing, Nemuri Seven?" Mayuri's golden eyes narrowed with curiosity.

The sounds she made were nothing more than gibberish, soft gargles and whimpers that were hardly intelligible. But the way she looked up at him was different. With those wide green eyes, she seemed to gaze right through him, past the hard exterior and the intellect. She didn't search the patterns he'd made with his black and white makeup to find something of interest. Nemuri Seven looked right into his eyes.

Mayuri pressed the release button and listened to the soft whoosh of air that accompanied the cylinder sliding open. For several long moments, he simply watched her. How her hands and feet seemed to not communicate with one another as she slapped and kicked at nothing.

Nemuri rolled onto her stomach and instead of lifting her face from the bedding, he watched more intently than before. Her small pale toes dug into the white blanket she laid on. Her chubby fingers grasped at the fabric bunched about her face. She struggled to move, to lift herself, and all he could do was tilt his head to the side and watch. Observe. Normally, he would have taken notes, he supposed, but then her head lifted and she looked around.

The air was suddenly filled with a grating, garbled cry that made Mayuri suddenly glad he'd implanted sound nullifiers in his golden ear coverings that activated when noise reached a certain decibel level. He could still hear her crying, but it was muffled enough that he wasn't tempted to smother her. That would defeat the purpose of this experiment after all.

"Oh, be quiet," he hissed. "Be happy you can breathe, you little wretch."

She kept crying. This was why he hated children. Babies, especially. They didn't understand a thing. They were too… he wasn't sure what, but he severely disliked it. Stupid, might be the right word.

With a soft sigh, he reached down into the bedding and picked up Nemuri Seven. Once she saw his face again, held at arm's length from him, she was silent. Her face had become a gentle pink from her agitation in such a short amount of time. He knew Nemuri Seven was a quiet infant. The other researchers made sure to note as much when they observed her in the first three months. There had been notations to find out if she was defective in some way, because she hadn't cried before - not that Mayuri thought it was a defect.

But as she looked at him, he wondered if there really was something wrong with her. "I would hate to have to discard you," he muttered. "All that work for…"

Her small hands raised and balled into even smaller fists, swinging at his face. Mayuri cautiously brought her closer, and went still when she grabbed onto a tuft of deep blue hair hanging down over his forehead. "What are you doing, Nemuri Seven?"

His only response was another gurgle and a soft tug. Mayuri pulled her away and glared at her, only to find her wide, toothless smile shining back at him. She giggled again and made a grab for his hair, catching the tip of his white-painted nose instead.

Mayuri held her close enough for her to explore his face with her hands, watching the keen interest in her soft green eyes all the while. She didn't seem to mind it when her tiny fingers came away from his face with smudged grey makeup on them. He did though. Luckily, no one was around and no one would  _be_  around until the early morning.

For the time being, he could allow his makeup to be ruined.

"That would be my eye," he said flatly. "You should be careful poking me. There are parts of me that are poisonous."

Not many, but he would be remedying that in the future.

She wiggled in his grasp enough for it to loosen. Purely on instinct, Mayuri pulled Nemuri Seven closer to his chest and braced her bottom with his forearm. And she laughed while tugging at the gold cone over his left ear. He would need to recalibrate it later on, but for the time being, Mayuri simply let Nemuri Seven do as she pleased.

This was the first human contact she'd ever had. He was curious to see what she would do with the time he spent with her like this.

* * *

Nemuri Seven was a year old. She'd made it an entire year and hadn't died, so Mayuri counted it as a win. A successful experiment.

Some nights, when he laid on the futon in his quarters adjacent to the lab, Mayuri considered Nemuri Seven's longevity to that point more than a successful experiment. He wasn't entirely sure what to call it though. This experiment, this project, had been one of many goals for him. And each day that passed with Nemuri Seven growing and learning - she had just started walking around the lab a week prior with only a small push cart holding files to keep her upright - meant another day that his dream had become a reality.

He'd really created a soul from nothing. He'd molded her himself. When he'd come across research materials from the human world that suggested physical contact promoted brain development and stability, Mayuri had tested it with Nemuri Seven.

The days when he would gently pat her head as he walked past her playpen, she was more docile. She slept better at night when she had at least three minutes of being held in his arms.

When he removed the stimulus, though, Nemuri Seven was a hellion. A spoiled little heathen that made him question his sanity when he'd embarked on the long journey to create her in the first place. She didn't cry if he was in the room, but the technician notes on her observations detailed her screaming fits while he was in captain meetings or out of the lab for more than an hour.

It was utterly mystifying, how something as simple as his fingers in her soft black hair would soothe his little test subject.

Mayuri sat up from his desk, stretching his back to ease the tightness that coiled between his shoulders from being hunched over his work. It was tedious but he needed to integrate a few more poisons into his zanpakuto and create an antidote. Just in case.

He looked at the clock on a shelf above his work space and carefully set everything down. It was late. Much later than he'd anticipated. He made his way out of the room and walked down the hall toward Nemuri Seven's crib just next to his computer. The soft green glow from the screen tended to lull her to sleep, much to his chagrin, so he kept it there and simply moved around it.

He may have put a file or two on her without thinking a few times. Nemuri Seven hadn't seemed to mind it.

When he found her lying in the crib, he hadn't expected her to be awake. Staring at him. And he definitely hadn't expected the foul smell that wafted up into his nose. He'd yet to create a machine that could teach her to use the bathroom like a civilized person, but he'd instructed Akon to handle it. Nemuri Seven had been trained to use the bathroom within the week. She didn't have  _accidents_. Mayuri refused to acknowledge her when she did.

Except she was looking at him and standing up in her crib. Trained or not, Akon had insisted that she be kept in diapers.  _Just in case_ , he'd said. Mayuri was at least thankful that his assistant had done that.

"Ma… Oo."

She reached over the edge of the crib, toward him, and Mayuri's lip curled in disgust as the scent grew stronger. There was only one thing he could do at that point. With no one around, it fell to him to deal with Nemuri Seven's excrement.

"I should have made Akon take you home with him," he said while lowering the side rail on the crib. He didn't try to help her get down, and instead watched her waddle toward the nearby bathroom. Curious, Mayuri followed.

He watched from the doorway as she removed her small yukata and diaper, then started to wash herself. She was only a year old, yet somehow she had the dexterity of someone older. Was this the first sign that she truly was an intelligent being? His eyes sparkled with wonder at the thought. Not only had he created Nemuri Seven from nothing, he'd made her intelligent.

Captain Unohana would be so jealous when he released the findings on Nemuri Seven's origin and progression. If Urahara were still around, he would be even more jealous of Mayuri's genius.

From what he understood of children Nemuri Seven's age, she shouldn't be capable of doing this yet. She was too young. And yet, he fully witnessed how thoroughly she cleaned herself. How much care she put into pulling on a clean diaper and disposing of the soiled one. It was only when Nemuri Seven needed to put her yukata back on that she struggled. She tried and tried, and Mayuri did nothing to help her until the little girl sat on the floor and started quietly sniffling with one arm pulled through the wrong sleeve.

Finally, he cleared his throat and drew her attention. "Nemuri Seven," he said, gazing down at her wide emerald eyes. "What's wrong?"

"Ooka," she whimpered, shaking her arm so roughly that the fabric fell to the floor. Her lips trembled while she stared at the crumpled mess. "Ooka."

"Yukata," Mayuri corrected. He watched her face crinkle and her cheeks redden. After watching her for another moment, he strode into the bathroom and knelt on the floor with a heavy sigh. "Honestly, you should be capable of this by now. It's simpler than what you just did."

She stood without prompting, and he ignored the tears trickling down onto her cheeks while securing her yukata around her small body.

"Back to sleep," he whispered. Mayuri walked out of the bathroom and went to the computer beside her crib. He still had work to do, print-outs from the day to read. Nemuri Seven was fully capable of getting back to sleep on her own.

He lost track of time once again as he read the reports on her progress. She had been difficult, apparently. Willful and too curious. There was a section of the lab that was quarantined from her spilling several vials when he'd been at a captain's meeting - that explained the odd smell when he'd returned - but her vitals had been checked and rechecked and she suffered no negative side effects. Two unranked shinigami hadn't been so lucky.

Interesting.

His eyelids began to droop, but there was still more work to be done. He could stay awake a little longer and get it finished. The times he slept in, no one questioned it. They never really knew if he was sleeping or performing experiments when the door to his quarters was closed. Minutes ticked by slowly and he felt exhaustion beginning to overwhelm him. Best to just take everything into his room, then. He could get changed into his own yukata and finish reading while lying on his futon, he supposed.

Mayuri stood and ignored the crib while going to the bathroom. He showered and washed the black and white makeup from his body, ignoring the few scars that had accumulated on his torso and arms from his latest enhancements. Once he was dressed, he returned to the lab to get his work and saw her. Still sitting up in her crib, with the railing still lowered. Staring at him.

"What?" he snarled. "I told you to sleep."

"Ma… Oo," Nemuri Seven babbled. "Ma-oo." She simply watched him as he picked up the papers he needed. "Ma-oo."

He turned away from Nemuri, papers in hand, and started to walk away.

"Dada…"

That had him stopping entirely and his lips twitching into a frown. "You will call me Mayuri-sama," he said.

"Ma-oo."

Mayuri's brows furrowed and he turned toward Nemuri Seven to find her still watching him. Except now she had the smallest little lift to her lips that almost resembled a smile. "Are you trying to say 'Mayuri'?" he asked.

"Ma-oo."

His eyes narrowed for a moment. That was wholly unexpected. Had she really called him her father simply to get his attention? Had she been saying her own form of his name all this time?

"Come with me, Nemuri Seven." He left the room and listened to her scrambled from the crib and toddle toward the sound of his slow steps. Once she was beside him, Mayuri reached down and gently grasped her small hand. "This way."

He led her to a nearby door and entered the code to open it. Just beyond was his bedroom, with his zanpakuto sitting on the work table in the far corner and his still-unfolded futon on the floor. He never saw the point in folding it, since he rarely used this room for much more than sleeping or sitting at the desk.

Mayuri led Nemuri to the futon and settled her beneath the blanket, placing his paperwork on the far side so he could reach it when he needed to. She stayed still while he pulled out a lantern and bathed the room in a gentle orange light from its flame. Nemuri Seven didn't say a single word - or her own versions of them - as Mayuri sat down on the futon and pulled a portion of the blanket over his legs. He picked up the paperwork and started to read, only to stop when he felt her staring at him.

"Sleep now," he said softly. He didn't want to think about why his voice didn't have the same venom in it while speaking to Nemuri Seven. "I brought you in here to sleep, not to stare at me."

"Ma-oo."

"What?"

Her small hand crept out from beneath the blanket and brushed across the tanned skin on his forearm. Mayuri looked down at where their flesh touched. How odd it felt to have such soft, gentle hands on him like this; her little fingers fluttering over his wrist and down to his hand. How had he created such a tender little soul? He looked at the papers he held, then back to her.

With a heavy sigh - that was partially forced only to make him feel a little more normal - Mayuri laid down on the futon beside Nemuri Seven and began to read aloud from the report. Maybe reading to her would make her sleep.

" _Nemuri Seven exhibits advanced cognitive functions. Brain scans indicate high gamma wave tendencies, though alpha and beta waves are prevalent..."_

Mayuri paused to look down at Nemuri Seven when she shifted beside him. "That means your testing is going well." She didn't respond, not that he expected much in the way of riveting conversation from her.

" _... Color recognition and spatial relations score: high. Recommend further testing…"_

"This looks good," Mayuri whispered, feeling Nemuri Seven shift once again. He waited until she was still, even though the little girl had partially crawled onto his arm, then continued reading the notes from her file.

" _... Reference DS.433.594.L for information on child speech development to cross-reference with observations of mean length of utterances for Nemuri Seven…"_

Mayuri yawned and finally gave up on trying to keep his eyes open. It was a lot of the same in varying degrees and fields. Nemuri Seven was outperforming their expectations time and again. He looked down at Nemuri Seven while setting the papers on the floor just beside the futon and found that she'd fallen asleep lying on top of him, with her ear pressed against his chest and drawing in the steady beat of his heart.

It may have been due to exhaustion, but he didn't want to move her. Instead Mayuri doused the lantern light and adjusted until he was comfortable with one arm beneath her tiny body, cradling her head against his chest.

Mayuri normally slept only on his back, but that night he fell asleep faster than ever before, lying on his side and gently holding Nemuri Seven in his arms.

* * *

There was a very precarious balance in their interactions that had to be maintained. No one could see that he favored this experiment over all others. He had to be distant during the day when Akon and other shinigami were around. At night, when it was just Mayuri and Nemuri Seven, when he removed his makeup and kept working in only a yukata and drank a cup of tea to keep himself awake, things were different. More relaxed, he supposed. It was something that Mayuri knew he would need to teach Nemuri Seven about as the days progressed. After that first night of having her sleep beside him, there were many more. Months upon months of restful nights for the Twelfth Division captain passed with his creation in his arms.

Even though she'd outgrown the crib beside his computer, and had her very own futon and bedroom near the lab, Nemuri Seven waited until the only shinigami in the building was Mayuri. Then she would sneak out and sit beside him while he worked. On occasion, Nemuri Seven would crawl up into his chair, right into his lap, and her gaze would trail across the pages he was reading or the multitudes of text on the computer screen; those nights, Nemuri Seven fell asleep in his lap and he was forced to carry her to his room when he was ready to sleep as well.

It seemed she didn't need an explanation for the appropriate times to seek his attention. Maybe this was some sort of intrinsic knowledge she'd gained during her incubation. It really didn't bother him. In fact, he encouraged it and her growth.

By the time Nemuri was two, he realized she was getting too big to really be carried by him. It wasn't her weight - which he knew was well within normal limits - but the fact that she was older. She was smarter. Nemuri Seven didn't  _need_  to be carried by him any longer.

And still, Mayuri found himself lifting her from the floor where she'd been toying with a wooden logic puzzle he'd discovered in his child-rearing research. He still held her in his arms and ignored the flutter in his chest when her arms wrapped around his neck.

"Mayuri-sama?"

"Yes, Nemuri Seven."

"Play game?"

Mayuri paused in his step to look down at her wide green eyes. They were so expressive, so full of curiosity. Because they were alone in this wing of the lab, he allowed a small smile to curl his lips. "I think you're old enough," he said while turning down a different corridor. "You can help me with an experiment."

"Ess-per-mint?"

"You'll see," he chuckled. Her head rested on his shoulder while he walked. She was always so relaxed in his arms. Finally, they reached room 6-F and he took her inside, right over to the metal examination table holding a particularly vicious hollow bear-like down with thick metal shackles and kido ropes. "This is a hollow, Nemuri Seven. Mindless beasts, but fascinating for research."

Nemuri Seven turned to look at the screeching hollow. "Hollow?"

"This one, in particular, has poison in its bite. A very potent poison that we're going to extract and analyze." He sat her down on the hollow's chest, smiling openly when it began writhing and trying in vain to break free and eat the suddenly giggling toddler. "Would you like to help me with this experiment?"

What he didn't tell her was that this was a two-fold test. She had far surpassed their expectations in normal scenarios for children her age. However, he wanted more than that for her. The only way to achieve that goal was greater exposure to different stimuli. There was so much advanced technology packed into her since her incubation had completed. He needed to test it now that her brain was developed enough to handle simple commands.

He took her hand in his and placed her fingers on the hole in the center of the hollow's chest. "This is a hollow hole," he said. "Destroying this will destroy the hollow." Mayuri pulled back and watched both of her hands dip into the hole, then retreat to touch the bone-white mask over its face. "That is the mask," he said.

Nemuri Seven was quiet and attentive as he spoke. She listened to his lecture about the properties of hollows, common weaknesses, markings that he'd discovered to determine what abilities they had.

Nemuri Seven moved down to the hollow's arm. Her eyes widened when her hand began spinning as though it was a drill and she looked up at Mayuri when he started laughing. "Extract some blood for me, Nemuri Seven. Don't kill it," he said.

She nodded and looked down at the hollow, striking its abdomen with her spinning hand. She seemed even more intrigued by the viscous crimson fluid bubbling up around her wrist.

"That would be its blood," he said. Mayuri pulled her hand from the hollow, lifting it for Nemuri Seven to see the blood-covered digits. "We'll test this for toxicity level. Come with me."

He didn't let her walk though. Instead, Mayuri lifted Nemuri Seven and carried her to a nearby table, then placed her bloody hand under a microscope for him to analyze. She stayed still without any prompting. She waited as he wiped her hand free of the blood and picked her up once more.

"Would you like to continue our experiment?" he asked.

Nemuri smiled up at him, and for the briefest of moments, Mayuri wanted to wrap his arms more tightly around her, to hold her closer than ever before with adoration seeping from him. But he held it back. It wouldn't do for her to grow too attached to him, after all.

* * *

Nemuri Seven was four years old and still sleeping on Mayuri's futon at night. Akon seemed to be the only one to realize that she was missing from her own quarters in the morning, that she was always by Mayuri's side when he first arrived in the lab. She shadowed him but made sure to stay out of his way. She helped him with his experiments, and he'd even begun teaching her how to wield a sword in the event he was incapacitated and she needed to use Ashisogi Jizo. As a created soul, she didn't yet show any particular powers that would be related to shinigami. Mayuri knew that only meant she most likely wouldn't have an elemental zanpakutou.

That day was her first real-world test. He had hollows to find and bring back for experimentation, and his subordinates had failed time and again to capture them. Nemuri watched from a safe distance while he incapacitated the hollows with ease. She walked right into the cloud of poisonous gas from his zanpakuto and emerged unscathed, dragging two previously conscious hollows toward him by their feet.

Four years old, and she was already so strong. So intelligent. And immune to the poison he used.

She woke up crying the first night he forced her to sleep in her own room, ripping Mayuri from his own sleep when she came barreling into his room. He groaned and tried to push her away, telling her to go back to sleep, but Nemuri Seven refused to budge. It meant he had to sit up and make her shut up. Except there was a sickening curl in his gut just from hearing her cry like that. Even when he asked what was wrong, she couldn't answer. And that wasn't like Nemuri Seven. She was more articulate than most adults, now that she'd learned how to speak more intelligibly. For her to be reduced to sobbing was unnerving, at best.

"Come here, you little brat," he sighed, picking her up and depositing her sideways on his lap. "Your crying is hurting my ears. Stop it."

She cried louder while she started trying to tell him what was wrong. He couldn't understand her though. Maybe this was a defect in her design. He really didn't want to discard her after putting four years of his time into her growth and development.

"Did you have a bad dream?" he yawned.

"Yes!" she sobbed.

Mayuri rubbed his eyes and let her latch onto him, seek comfort from his closeness. "Is it because you were alone?" She didn't answer, but he knew that had to be the truth. For the past three years, he'd allowed Nemuri Seven this single vice. She was allowed to sleep next to him. He wasn't going to admit to anyone that he hadn't been sleeping very well the past few hours without her so close. Still, she needed to learn that she couldn't sleep beside him any longer. She was getting older, and she was nothing more than a successful experiment. He didn't allow the hollows he dissected to crawl into bed beside him, so why should Nemuri Seven be any different?

But she was different. She was the embodiment of his biggest goal to date. No matter how many experiments he performed, no matter how long he spent searching for more knowledge and trying to answer questions far beyond any normal soul's reach, Nemuri Seven was special. Created from nothingness. He'd made her, sculpted her, molded her very existence. She learned so much, and so quickly, that he could hardly stand it. Only because he knew what this meant.

He'd succeeded where so many others had failed. Every day he looked at Nemuri Seven, Mayuri remembered how hopeful he'd been when he'd seen her gestation begin. He remembered watching her through the glass cylinder that was her incubator, how she'd grown so slowly at first and made leaps and bounds as the months progressed.

"You can stay here," he whispered. His fingers sifted through her tousled black hair, and his lips lowered to the top of her head. "Stay with me."

"Thank you, Mayuri-sama," she whimpered.

A small smile twitched on his lips before they puckered on the top of her head. She didn't seem to notice, or maybe she just didn't call any attention to it. "I'll protect you," he said. "No bad dreams will get to you in here."

"P-Promise?"

They laid down together and he sighed while she curled up against him, just like she always did with her ear over his heart. It felt oddly right to have her in his arms again while he drifted off to sleep. "I'll use my bankai to poison any who try," he yawned. "And then we can catch those bad dreams and inject them with the drugs I've been making… Observe them and see how the bad dreams react…"

"Goodnight, Mayuri-sama," she giggled. He didn't see the serene smile on her young lips while her eyes closed and she snuggled closer. Just as he didn't see her smile grow when he spoke again.

"Goodnight... my little Nemu."


End file.
